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February 2021 Tarsus Issue No. 614 CIRCULAR OF THE ENTOMOLOGICAL SOCIETY OF NEW SOUTH WALES Inc This month’s member spotlight is our journal editor Dr Robin Gunning. For most of her career Robin was based in DPI Tamworth where she specialized in insect resistance, amongst other endeavours, and remains a world expert in the management of insect resistance. This month we also publish the four submissions for the inaugural Ted Taylor prize, won by Joshua Whitehead from University of New England on the relationship between mirid bugs and carnivorous plants. Joshua has received the $1000 prize and all participants have been given free membership to the society for 2021. Recently, many of you may have read that Geoff Monteith, a Queensland based member of our society, was named among the top ten scientists as measured by the number species named after him – in the same league as Charles Darwin. A quick scout of our other members revealed some others that have also been honoured. Happy reading. This month, in the Photo Corner section, there is a feature on cossid moths generated by the interest of young member Ambrose with some fantastic photos. We continue providing hyperlinks to entomological stories and research that may be of interest to members. Kind Regards Garry Webb Circular editor www.entsocnsw.org.au TARSUS No. 614 February 2021 Page 1 Member Spotlight DR. ROBIN GUNNING I’d always been one of those kids who was fascinated by the natural world but never dreamt it could become my career. However, whilst doing an Arts degree at the University of NSW I found that the compulsory science subjects (biology and invertebrates) were far more interesting than the history and political science I was meant to be studying. I had discovered the insidious charm of insects and resolved to make entomology my career. So, after graduating with that BA, I took a job as a technical assistant in the analytical chemistry section at the Australian Atomic Energy Commission and studied part time for a science degree at the University of NSW, majoring in chemistry and entomology. My entomology studies were with Dr Erik Shipp. I went on to graduate with Honours Class 1 in Entomology. Having picked up a Commonwealth Postgraduate Research Award, I quit my job and enrolled in a PhD in entomology at the University if NSW with Erik Shipp as my supervisor. I’d always had a physiological bent, so the title of my thesis was “A Circadian rhythm in the Eye Nerve Activity from the Housefly, Musca domestica”. Doing a PhD at the Randwick entomology labs in the company of entomology staff and students was tremendous fun and I made friends for life. At the end of my PhD, I was astounded to receive a job offer from the NSW Department of Agriculture as Entomologist based at the Tamworth Agricultural Research Centre and I thought I’d better take it. Here I found a background in chemistry as well as entomology was very useful. I became a specialist in insecticide resistance and the chemical control of insect pests in field and horticultural crops. In particular, I worked on the control of Helicoverpa spp. and Bemisia tabaci on cotton. I published extensively in the areas of insecticide bioassay, insecticide application, synthetic and biological insecticides, insecticide resistance management and in the mechanisms of insecticide resistance. I am a world authority on the management of insecticide resistance. Of particular interest to me was my long-standing collaboration with Dr Graham Moores of Rothamsted Research in the UK, involving biochemical mechanisms of insecticide resistance and the binding of insecticides and insecticidal proteins, such as Bt, to esterase isoenzymes. My research resulted over 50 refereed publications and two international patents. I supervised some 10 higher degree students in entomology. I retired from the Department of Primary Industries in 2015 as Principal Research Scientist and I remain grateful to those bosses who saw the value of research and encouraged me. I have other interests in entomology as well. For a time, I was convenor of the Australian Entomological Society’s Conservation Committee. I was a member on the NSW Scientific Committee, (convened under the Threatened Species Act, 1995) from 1996-2003, which was a most rewarding experience. I’m also Editor of General and Applied Entomology which is the journal of the Entomological Society of NSW. It is a real privilege to assist authors in the publication process. www.entsocnsw.org.au TARSUS No. 614 February 2021 Page 2 Ted Taylor Entrants The relationship between mirid bugs and carnivorous plant species – Is it parasitic, commensal, or mutualistic? Joshua Whitehead University of New England Armidale Abstract: An unknown number of species of Hemipterans (true bugs) in the tribe Dicyphini (Miridae) have been found to live in close association with carnivorous and protocarnivorous plant species. However, the nature of these relationships has been difficult to determine, often as a result of contradictory behaviours and perceived impacts. Here I discuss the impacts of known carnivorous plant-bug interactions to determine whether they are parasitic, commensal, or mutualistic in nature. Introduction: Mirid bugs (Miridae: Hemiptera) are a speciose group of insects known as ‘true bugs’ (Heteroptera) that use piercing mouthparts to extract nutrients from plants and other insects. Most widely known species are considered pests in agriculture (e.g. Lygus hesperus) whose feeding habits cause significant damage and spread viral plant diseases. However, a few species are mostly predatory and are valued as biocontrol agents (e.g. Dicyphus hesperus), despite being omnivores that will die when deprived of their host plants (Gillespie and Mcgregor 2000). This omnivorous feeding behaviour may have prompted some groups in tribe Dicyphini (Pameridea and Setocoris spp.) to evolve in close association with carnivorous host plants. For today there are a number of Dicyphini specialised for life on carnivorous plant species (e.g. Byblis, Drosera, Roridula, and Stylidium spp.). Known only from the Western Cape province of South Africa and Australia, these bugs are extremely well adapted to living on sticky surfaces, and therefore able to negotiate their way through the sticky secretions of their host plants. This enables them to feed on the other insects caught by their host plant, in a behaviour that is often called as kleptoparasitism (parasitism by theft). However, the nature of this symbiosis becomes considerably more complex when you consider that such behaviours may help the host plant. For instance, by reducing the number of prey items, the bugs can prevent plants being overburdened, which can lead to a nutrient overload and die-back in carnivorous plant species. Meanwhile, in protocarnivorous plant species like Roridula and Stylidium, the bugs are more likely to be commensal (benefiting without affecting the host plant) or beneficial (mutualistic). Since these protocarnivorous plant species lack the enzymes to digest insects, meaning they derive no direct nutritional benefit from trapping insects. Here I’ll discuss the behaviour and likely impacts of two mirid bug genera (Pameridea and Setocoris) that are known to live in close association with insect trapping host plants, with the ultimate aim of determining whether they’re parasitic, commensal, or mutualistic on their chosen host plants. Pameridea: Pameridea is a genus of two described bug species (P. marlothii and P. roridulae) that live in close association with plants in the genus Roridula. Pameridea marlothii occurs exclusively on R. dentata, while P. roridulae has a facultative (non-exclusive) preference for R. gorgonias. Endemic to the www.entsocnsw.org.au TARSUS No. 614 February 2021 Page 3 western cape of South Africa, both species feed on insects caught by the host plants, which possess leaves that are covered in sticky resin-tipped trichomes (hairs). If there is an absence of insect prey, Pameridea will often feed on the host plant, avoiding capture with specialised feet and a thick, waxy epicuticle (Voigt and S. 2008). Females lay eggs directly into the tissues of a host plant, and in the absence of a host Pameridea enter diapause (dormancy) or die of starvation. This implies that Pameridea may be wholly dependent on the host plants (obligate symbionts), and maybe a risk of co-extinction in their absence. Initially thought to be parasites, several nitrogen tracing experiments have shown that Roridula may be unable to digest insects (Ellis and Midgley 1996). This suggested the relationship with Pameridea may be commensal (neutral), as initial observations implied that Pameridea may pollinate Roridula (Ellis and Midgley 1996). However, like most carnivorous plant species, Roridula have a poorly developed root system and grow in heavily leached acidic soils in wet conditions. They also possess leaves that strongly absorb the primary wavelengths of ultra-violet (UV) light, which are assumed to attractant to flying insects to carnivorous plant species. It has been therefore suggested that Roridula still benefits from trapping insects, despite an inability to extract nutrients from them. Instead, subsequent tracing experiments using the rare isotope nitrogen-15 have shown that Roridula can absorb nutrients from Pameridea faeces (Ellis and Midgley 1996). Meaning that the bugs serve as a surrogate in digestion of captured insects, removing carbohydrates and proteins, and leaving nitrates. Resulting in a mutually beneficial arrangement for both plant and insect species, since the carbohydrates and proteins are of no use to Roridula. Setocoris: Setocoris is a genus of three described mirid species (S. bybliphilus, S. droserae, and S. russelli) that are known to occur on plants in the genera Byblis, Drosera, and Stylidium. Currently they are endemic to all states and territories of Australia, though there are numerous colour morphs and potential variants that await description. All Setocoris species feed on insects caught by their host plants and like Pameridea, will feed on the host when these are absent.